These are just for fun, but I thought of making up songs based on the ones from the South Park movie. Still working on lyrics: Mountain Town - School of Magic (Harry, others)
Uncle F***a - Muggle F***a (Malfoy, insulting Hermione)
It's Easy, Mmkay - It's Easy, Ok (Lupin, teaching DADA)
Blama Canada - Blame Voldemort (undecided)
Kyle's Mom is a B***h - Dolores Umbridge is a B***h (Fred & George)
What Would Brian Boitano Do? - What Would Albus Dumbledore Do? (Harry, Ron, and Hermione)
Up There - Out There (Arthur Weasley, about Muggle world)
La Resistance - Order of the Phoenix (Sirius)
I Can Change - I Have Changed (Snape)
I'm Super - I'm Lockhart (Lockhart)
Mountain Town Reprise - School of Magic Reprise (Hagrid, rest of cast)
Anyone else have ideas?